Both give you an extra turn for 5 mana, which means another attack, land drop, and draw step all rolled into one
That means it can't be countered by spells like Essence Scatter (which counters strictly creature spells) but can be stopped by something like Negate (which strictly counters non-creature spells)
Landfall Whenever a land you control enters, you gain 4 life if this is the first time this ability has resolved this turn
But some of the richest experiences Ive had in EDH have been with decks that are imperfectly optimized, or off kilter, or, for a lack of a better word, weird
Alliances would continue this theme (Winter's Night), but we'd then have to wait until 2006 before Wizards of the Coast would complete the block with Cold Snap, which formally established the Snow supertype
While the main booster set itself doesn't contain any new cards, the 4 preconstructed companion decks released alongside it each have 10 new ones so we will be giving our thoughts on these additions to our favorite format